1. Field of the Invention
The present invention relates to network data processing, and particularly to a method of interfacing data packets between real and virtual networks when carrying out hardware in the loop simulations.
2. Discussion of the Known Art
During development of communication (e.g., radio) and other networking hardware devices, only a limited number of actual prototypes are ordinarily available for testing. Because of this, it is difficult to test the prototypes exhaustively to confirm that a large number of the devices can communicate effectively with one another under various conditions over a real network. Therefore, an alternative approach toward testing has been adopted that involves modeling of the hardware specifications, and simulating the modeled specifications within a virtual network under a variety of conditions using a commercially available discrete event modeling tool such as, for example, OPNET Modeler® available from OPNET Technologies, Inc. (hereafter “OPNET”).
A number of disparities may exist between the actual (real) hardware and its modeled specifications, however. Such disparities can have a significant impact on resources and production costs if not detected early on. Accordingly, there is a need for a bridge or technique to correlate real network devices (i.e., actual hardware) with their virtual models so as to reduce or eliminate disparities, and to improve the validation process for the devices.
Work has been performed toward interfacing real network hardware with an OPNET simulation for the purpose of evaluating individual network components as well as entire networks. See R. Martínez, et al., “Modeling & Simulation of Hardware-in-the-Loop Using OPNET Process Models”, OPNETWorks Symposium, Washington, D.C. (August 2002); K. M. McNeil, et al., “HITL/SITL Generic Reference Model”, OPNETWorks Symposium, Washington, D.C. (August 2003); and R. Martínez, et al., “Hardware and Software-in-the-Loop Techniques Using the OPNET Modeling Tool for JTRS Developmental Testing”, MILCOM 2003 (October 2003). All relevant portions of the three mentioned articles are incorporated by reference.
The prior work uses the of sockets for extraction and insertion of data packets between simulated networks. That is, a TCP socket connection is used to send traffic, thus requiring a one-to-one mapping between two simulations. For example, simulated network A must create a specific TCP socket to simulated network B before sending data to network B. If network A wants to send data to simulated network C, then network A must create a new socket connection specifically for network C. Moreover, the known technique supports the exchange of packets only between simulated networks.